it's sorta illegal but not really enforced, basically spray painting a clear gun is making it into a replica firearm, which is against the law, whether they enforce this law remains to be seen, haven't hear of anyone being arrested for that.

now if you used this painted gun in the commission of a crime, then that would add to whatever they charge you with, try using the search next time, we don't like lazy people 'round here

Most cops are usually entertained by black guns, don't really confiscate them. Just exercise with them with extreme caution. You'll be fine. Never act nervous around police either when this kind of situation comes up, otherwise they assume you're up to no good. There've been plenty of people on ASC who have been puled over for say speeding (Late for a game, probably) and had the gun in it's case in the back seat, the cop sees the case, and the driver openly admits it's an airsoft gun. Mind you, you may get the asshole cop who convicts you for holding a prohibited item.

Just be wary. When you're transporting it, don't break any rules (cutting people off, speeding, shit like that). If you get pulled over by a cop for that and they ask to know what's in the bag, you could get in some pretty big shit.